No, "our" Syaoran shouldn't be gone forever. ^_^  I mean, that scene at the beginning of volume one might happen, right?
There's a lot of good theories running around the internet. (And probably some of my own.)
1) R!Syaoran is actually lying to C!Syaoran in order to get C!Syaoran's "heart" to somehow go back to normal. (Edit: Although C!Syaoran doesn't really have a "heart" now, that doesn't mean his "love" has faded or did it really go away?)
2) The volume one prelude scene in that giant tube might actually be a "dream"?
3) R!Syaoran would eventually learn to fall in love with Sakura even if he had no feelings for her before.  (So technically, he would become "our" Syaoran again because his heart was reflected in the clone.)
4) C!Syaoran's heart will be able to revert to "our" Syaoran again. Problem with this theory is his "program" that's embedded with him unless he can root it out (and become a real boy! Like Pinocchio!)
5) Most common theory ---> R!Syaoran and "our Syaoran will merge. >_>  In one mind, body, spirit, etc.
6) What if the yin/yang seal actually had two parts to it?  Even though we assume that the seal went fully back to C!Syaoran before R!Syaoran retrieved it.  What if, Fai actually had some other part of it, still?
7) Sakura's voice will awaken "our" Syaoran somehow??  O_o
 Something interesting that I read from the MSN TRC manga board.  Syaoran's price was supposedly his "relationship" with Sakura. BUT....it may have been the other way around!!  Syaoran's price was to forget his "love" with her. ^_0
And that's all I've seen so far.  Good things to brainstorm as we countdown to Wednesday. Â